Marine engine corrosion prevention system

ABSTRACT

An apparatus and method for prevention of corrosion with the cooling system of an internal combustion engine is disclosed. The apparatus includes a pressurized inert gas source and a fluid delivery system whereby the gas is dispersed within the cooling system to expel corrosion inducing fluids such as oxygen and water vapor. Methods of use are also disclosed.

BACKGROUND OF THE INVENTION

The present invention relates to an apparatus and method for inhibitingcorrosion, and more particularly to a new and improved apparatus andmethod that prevents the corroding of cooling fluid passageways andother surfaces of internal combustion engines during storage orprolonged periods of non-use. This is accomplished by removingsubstantially all of the oxygen and/or water vapor from the passagewaysand surfaces.

Internal combustion engines generate power by controlling multiple,successive explosions of a combustible fuel within one or morecombustion chambers. The process generates not only power through thepower take off component of the engine, but also heat. The heatgenerated during the process must be dissipated from the engine to avoidcatastrophic failure of the engine or its components. Smaller enginestypically dissipate heat through the flow of air across the engine.Air-cooled engines include cooling fins to increase the efficiency ofthe cooling process. This is commonly referred to as convection cooling.Engines used in the lawn and garden industry to provide power for lawnmowers, snow throwers, chain saws, etc. are commonly air-cooled.

Larger engines utilize a liquid fluid, such as water or water incombination with other ingredients for cooling purposes. Specifically,these larger engines include one or more fluid-tight passageways locatedwithin the engine and around the exterior of the engine to serve thispurpose. Since the majority of the heat is produced in the combustionchambers, the majority of passageways are formed about this area of theengine. This structure is sometimes referred to as the water jacket.

Liquid fluid cooled engines can be further classified into twocategories: closed loop systems and open loop systems. Closed loopsystems circulate a predetermined amount of liquid fluid through theengine and a heat exchanger, such as a radiator. A pump is provided tocirculate the liquid fluid. The fluid is commonly referred to ascoolant. The fluid absorbs the excess heat around the combustion chamber(and elsewhere) of the engine and then dissipates or cools the fluid inthe heat exchanger. As the system is closed, no new or additional fluidis added or removed from the system during cooling (i.e. engineoperation).

An open loop system also includes a pump, but by contrast the open loopsystem draws the cooling fluid from a fluid source, circulates the fluidthrough the cooling system and then expels the fluid back to the source.This type of cooling system is commonly used on marine engines such asoutboard engines, inboard engines and inboard/outboard engines. In thecase of a marine engine, the cooling fluid comprises the body of waterwithin which the boat utilizing the engine is situated. A common problemwith an open loop cooling system is that the cooling fluid (i.e. water)includes all of the contaminants and corrosive components that exist inthe fluid. For example, a marine engine operating in a salt-waterenvironment is subject to the corrosive nature of the salt thataccumulates in its cooling system.

The corrosive nature of salt in marine engines can ultimately lead todestruction and/or catastrophic failure of the engine after prolongedexposure to salt. To combat this problem, boat owners and operatorstypically “flush” their cooling systems by providing a fresh watersupply at the engine's cooling fluid intake and operating the engine fora predetermined amount of time to flush the salt water and residual saltfrom the cooling system. It is desirable to flush an engine as soon aspossible after operation in a salt-water environment so that thecorrosive salts can be immediately removed. It is imperative that thesalts be removed before the salt water cools and dries within thecooling system thereby forming salt crystals within the passageways andon the interior surfaces of the engine cooling system. A galvaniccorrosive reaction occurs between the salts, oxygen, water vapor andmetal engine components. If not terminated, the corrosion will continueleading to the ultimate destruction of the engine component or a portionthereof.

With respect to marine engines, it is known in the art to elevate a boaton a lift after operation in a salt water environment, connect a freshwater source to the cooling system intake and operate the engine for asufficient time period in an attempt to remove all salt water andresidual salt from the cooling system. Depending upon the specific typeor style of marine engine, many companies manufacture devices that canbe easily and temporarily coupled to the engine's water intake port.Such devices also include an coupling or fitting that is connected to agarden hose or similar supply line. The opposite end of the hose isconnected to the fresh water source.

While this method and apparatus can also be used for marine engines thatare still submersed in salt water, the removal of salts from the coolingsystem is much less effective as salt water is likely to leak into thecooling system during flushing as well as upon completion of theflushing process.

While this common flushing process is generally accepted as the bestremedy for the removal of salt water from the engine's cooling system,it is known that the process does not remove all salt from the system.The flow of fluid through the cooling system is often such that thereexist pockets or areas where the fresh water is either not circulated ornot circulated in sufficient quantities to remove all of the salt. As aresult, at some point in time the marine engine will be damaged or faildue to corrosion.

Additional drawbacks to the accepted method of flushing include thenecessity of removing the boat from the water on a lift or rack,accessibility to a plentiful fresh water source, the necessity ofoperating the marine engine during the flushing process and the amountof time it takes to complete the flushing process.

Another known flushing system for marine engines is disclosed in U.S.Pat. No. 6,579,136 to Hahn, et al. This system includes a reservoir, adispenser and a connection device. The reservoir is filled with aprotective liquid fluid that includes anticorrosive properties. Thedispenser allows for controlled release of the protective liquid fluiddirectly into the engine's cooling system downstream of the engine'swater intake. The boat operator can release the protective fluid intothe cooling system as needed (i.e. prior to storage of the boat).

SUMMARY OF THE INVENTION

The general purpose of the present invention is therefore to provide acorrosion inhibiting apparatus and method which are easy to practice,and which will effectively reduce the tendency of corrosion toaccumulate upon the inaccessible surfaces and passageways of an internalcombustion engine cooling system. The method has been design to berelatively simple and short, while obviating the difficultiesencountered in the practice of prior art processes. To attain this, thepresent invention contemplates an apparatus for the introduction of aninert gas into the interior cooling system or water jacket of aninternal combustion engine, typically somewhere near the highest pointof the cooling system. The process is continued by allowing the inertgas to circulate throughout the entire cooling system until allcorrosion inducing fluids, such as oxygen and water vapor are expelledthrough the engine's cooling system intake and exhaust output ports.Finally the inert gas is retained in the system for the length of timeit is desired to preserve the cooling system. In addition, ananticorrosive material may be mixed with the inert gas prior tointroduction to increase the efficacy of the system. By using an inertgas that is lighter than air, oxygen and water vapor, all of the keyelements critical to corrosion are displaced from the system due to thebuoyancy of the purging fluid (i.e. inert gas).

The apparatus includes a source of inert gas, a pressure regulator, avalve and a connector. All four components are fluidly coupled in seriesthrough a suitable conduit or hose. A mating connector is attached tothe engine cooling system, again ideally near an uppermost portion ofthe engines cooling system. The mating connector may remain permanentlyconnected to the engine. The apparatus connector is connected to themating engine connector after the engine has been stopped. After thepressure regulator has been properly adjusted, the valve is opened for apredetermined period of time to permit the inert gas to flow and fillthe cooling system. During the filling process, all oxygen and watervapor are dispelled or forced out of the system through either theintake or output ports. In an alternate embodiment, a source ofanticorrosive material is provided along with a mixing device to combinethe inert gas and anticorrosive material prior to the introduction ofthe mixed compound into the engine.

The inert gas can comprise any gaseous fluid other than oxygen andhydrogen and ideally is a gaseous fluid that has an atomic weight lessthan that of oxygen and water vapor. The preferred inert gas is helium.The amount of helium required to purge the cooling system of oxygen andwater vapor is significantly less than other inert gases due to helium'slow atomic weight and hence its natural buoyancy in comparison to air.Helium also prevents the possibility of air leakage back into awatertight system. Another suitable inert gas is nitrogen. However theuse of nitrogen would require a greater quantity to be introduced intothe cooling system due to the fact that nitrogen has an atomic weightonly slightly less than that of air. In addition, the inert gas may alsoinclude those gases that are completely chemically non-reactive such asargon or Freon. Because these inert gases are have an atomic weightgreater than that of air, these gases must be introduced from the bottomof the engine cooling system or combustion chamber. It is to bespecifically noted that this reverse purging method falls within thescope of the present invention.

The anticorrosive material can comprise a lubricant or a biodegradablematerial. Suitable lubricants include commercially available foggingoil. Vegetable oil may also be used as a biodegradable anticorrosivematerial.

It is important to note that because an inert gas is utilized in thepreferred embodiment of the invention, the system may be used at anytime after engine shut down. Unlike the prior art processes, the engineneed not be in operation during introduction of the inert gas. Becausethe preferred gas is non-reactive or inert, the gas can be introducedinto a hot engine (i.e. there is no need to wait for the engine to coolbefore introduction of the inert gas into the cooling system). Theapparatus and method of the present invention may be used on a marineengine that is in the water, on a marine engine that has been removedfrom the water or on any other fluid cooled engine.

An object of the present invention is to provide a corrosion inhibitingapparatus and method in which the potential for galvanic corrosion ischemically terminated, so as to prevent the accumulation of corrosionwithin the interior of an internal combustion engine cooling system.

Another object of the present invention is to provide a corrosioninhibiting process in which all water, oxygen, salts, and othercorrosion causing materials are removed from the cooling system of aninternal combustion engine by the introduction of an inert non-corrosivegaseous fluid.

A further object is to provide a strategically placed and easilyaccessible coupling within the cooling system for introduction of thebuoyant, inert gas into the cooling system.

Another object of the invention is to provide an apparatus that canprovide the inert gas for a predetermined period of time or in apredetermined quantity.

A still further object of the invention is to provide dual protectionfrom corrosion for the cooling system of an internal combustion engineby providing an anticorrosive protective film coating for the coolingsystem while retaining an atmosphere of inert gas.

Other objects and advantages of the invention will hereinafter becomemore fully apparent from the following description of the drawings,which illustrate a preferred embodiment of the apparatus by which thepresent invention may be practiced.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the corrosion prevention system.

FIG. 2 is a perspective view of an alternative system.

FIG. 3 is a perspective view of another alternative system.

FIG. 4 is a view of the system connected to an outboard marine engine.

FIG. 5 is an exploded, partial view of the marine outboard engine.

FIG. 6 is another exploded, partial view of the marine outboard engine.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Although the disclosure hereof is detailed and exact to enable thoseskilled in the art to practice the invention, the physical embodimentsherein disclosed merely exemplify the invention that may be embodied inother specific structure. While the preferred embodiment has beendescribed, the details may be changed without departing from theinvention, which is defined by the claims.

Referring now to FIG. 1, reference numeral 10 is used to indicate theapparatus of the present invention. The first component includes acylindrically shaped tank 11 containing a supply of inert gas. Preferredinert gases for the purpose of the present invention include helium andnitrogen. The inert gas is retained within tank 11 under high pressure,and when it is desired to use the apparatus, valve 12 is opened tointroduce a supply of gas into the system herein after described. Aconventional pressure regulator 13, having the usual pressure gauge 14,is provided in the system 10 adjacent tank 11, and is adapted to controland limit the pressure of the inert gas to a maximum level, such as, forexample, 100 pounds per square inch (psi). In order to work effectively,the inert gas flow must be regulated to gradually displace all corrosioninducing fluids in the cooling system without creating an undue pressurebuildup in the cooling system. A relief valve 15, which is actuatable ata set predetermined pressure such as 120 psi, is provided in the system10 adjacent regulator 13 to act as a safety device. A flexible hose 16extends from relief valve 15 to a pressure gas jet eductor 17 connectedto an anticorrosive material tank 18, which is adapted to be mixed inits venturi (not shown) with the supply of inert gas from the tank 11.When the valve 19 of tank 18 is opened, the high velocity inert gasatomizes the liquid withdrawn from the anticorrosive material tank 18into the venturi and creates an anticorrosive protective film coating or“fog” for coating the internal surfaces of the cooling system. Apressure gauge 20 is connected in the system adjacent tank 18, and issuitably provided with a pressure relief valve 21. A shut-off valve 22is provided in the system 10 adjacent gauge 20, and is connected by aflexible hose 23 to a high pressure quick connect coupling or fitting 24utilized to convey the inert gas and anticorrosive material through amating cooling system coupling 25 attached to the cooling system 26 ofan engine 33 to be preserved (see FIG. 4).

In an alternate embodiment shown in FIG. 2, a “Y” fitting 28 may beprovided in flexible hose 23 to allow the system 10 to be provided withtwo outlet couplings 24 a and 24 b. This arrangement is best used for anengine having two cylinder banks or heads (not shown).

In yet an another embodiment, designated 10 a and as shown in FIG. 3,the handle of valve 22 may be replaced with a solenoid 31 connected to aprogrammable controller 32 for automatically dispensing the inert gascontained within tank 11 and corrosion inhibitor contained within tank18 into the engine cooling system 26. The controller 32 may furtherinclude a timer (not shown) that can be programmed to allow the inertgas and anticorrosion material to be dispensed for a predetermined timeperiod. In addition or alternatively, the timer may be programmed todispense inert gas and anticorrosion material at a predetermined time orat predetermined time intervals. The valve 22 may also include a flowmeter (not shown) connected to the controller 32 that can be programmedto dispense a predetermined amount of inert gas through the system 10 a.

FIG. 4 shows the system 10 or 10 a connected to a marine outboard engine33. The present invention has a further advantage in its application toan outboard marine engine 33 in that the inert gas may be easilyintroduced into the interior of the engine cooling system 26 at the topof the engine 36. As shown quick disconnect coupling member 25 is influid communication with the cooling system 26 of the engine 33. Thequick disconnect coupling member 25 is of a type that is known in theart and that mates with the coupling member 24 attached to the distalend of hose 23 in the apparatus 10. When coupling 24 and coupling 25 areconnected, a fluid tight connection is formed. While it is preferredthat the coupling member 25 in fluid communication with the engine'scooling system remain in the engine once installed, the coupling 25could be removed and replaced with a plug (not shown).

The coupling 25 could be placed anywhere in the cooling system 26,however it is desirable to place the coupling at the highest point ofthe cooling system 26 as shown. This allows the inert gas to dispel allfluids containing corrosion-inducing materials such as oxygen and watervapor to the bottom of the cooling system where they are dispelledthrough the cooling system intake 34 and the exhaust output 35.

The method of the present invention includes the steps of installing acoupling in fluid communication with the cooling system of an engine,connecting a source of pressurized inert gas to the coupling anddispensing a predetermined amount of gas into the cooling system.Alternatively, the inert gas may be dispensed for a predetermined amountof time. In addition, the method may further include the step ofproviding an anticorrosive material and mixing the material with theinert gas prior to dispensing the mixture into the cooling system.

The preferred inert gases include helium and nitrogen. Alternate inertgases include argon and Freon. The preferred inert gas should have anatomic weight that is less than the atomic weight of corrosion inducingmaterials that are sought to be purged from the cooling system such asoxygen and/or water vapor and should be introduced into an upper portionof the engine. When the inert gas is introduced into the cooling system26 of an internal combustion engine, the gas will quickly becomedispersed throughout the entire cooling system 26 of the engine and willdisplace air (including oxygen) and water vapor residing within thecooling system 26. While the inert gas will initially rise to the top oruppermost portion 36 of the cooling system 26, as the volume of gasincreases and accumulates within the system the inert gas will force theoxygen and water vapor out of the system through the cooling systemopenings including the water intake 34 and exhaust outlet 35. Byremoving the oxygen and water vapor from the system 26, the potentialfor the formation of corrosion within the cooling system is alsoeliminated.

Alternatively, an inert gas that has an atomic number greater that thatof air can also be utilized. However, it is preferable that these inertgases be introduced into a lower portion of the engine cooling system.

As shown in FIG. 5, for long periods of storage, the cooling systemintake port 34 and exhaust port 35 of the engine 33 can be suitablysealed with adhesive tape 37 (or a similar material) to retain thecorrosion inhibiting atmosphere of inert gas within the interior of theengine cooling system. Alternatively, and as shown in FIG. 6,conventional plugs 38 can be installed in the intake port, 34 andexhaust port 35. It is also contemplated that the inert gas could bereintroduced to the engine cooling system at a later time during aprolonged storage period. Utilizing the controller 32 in conjunctionwith solenoid valve 31, this may be accomplished automatically.

De-preservation of the engine preserved by the present apparatus andmethod is accomplished by merely starting the engine in the water toflush the inert gas from the cooling system.

The apparatus and method set forth above can be applied to all types ofengines that may be stored for prolonged periods of time includingengines that have closed loop cooling systems such as automobile, truckand aircraft engines. The inert gas would be dispelled into the coolantinlet of the engine while oxygen and water vapor would be expelledthrough the coolant outlet. Again, the inlet and outlet may be sealedafter the introduction of inert gas is complete to retain the inert gasenvironment within the cooling system. In addition, many modificationsand variations of the present invention are possible in the light of theabove disclosure. Anyone skilled in the art of preserving machinery canreadily see that this method could equally preserve tanks, heatexchangers, compressors, pumps, turbines and other types of processequipment or the like.

The foregoing is considered as illustrative only of the principles ofthe invention. Furthermore, since numerous modifications and changeswill readily occur to those skilled in the art, it is not desired tolimit the invention to the exact construction and operation shown anddescribed. While the preferred embodiment has been described, thedetails may be changed without departing from the invention, which isdefined by the claims.

1: An apparatus for purging corrosion inducing fluids from a coolingsystem of an internal combustion engine during storage comprising: asource of inert gas having an outlet; a first coupling attached to saidoutlet; and a second coupling in fluid communication with the coolingsystem whereby the first coupling is adapted to be removably coupled tothe second coupling. 2: The apparatus of claim 1 wherein the source ofinert gas comprises a pressurized tank. 3: The apparatus of claim 1wherein the inert gas is selected from the group consisting of heliumand nitrogen. 4: The apparatus of claim 1 further including a pressureregulator attached to the outlet. 5: The apparatus of claim 1 furtherincluding a source of anticorrosive fluid, said source of anticorrosivefluid being in fluid communication with said source of inert gas. 6: Theapparatus of claim 5 further including a mixing device, said mixingdevice located at the fluid communication of the anticorrosive fluid andthe inert gas. 7: The apparatus of claim 1 wherein the first and secondcouplings are quick disconnect couplings. 8: The apparatus of claim 1further including a valve, said valve being attached to the inert gasoutlet. 9: The apparatus of claim 8 wherein said valve is a solenoidvalve. 10: The apparatus of claim 9 further including a programmablecontroller, said controller being connected to said valve. 11: A methodof inhibiting corrosion on the interior surfaces of an internalcombustion engine cooling system during storage comprising the steps of:connecting a source of pressurized inert gas to an intake port formed insaid engine; dispersing said inert gas into said engine cooling systemthrough said intake port formed in said engine; and purging corrosionproducing fluids from said engine as said inert gas is dispersed intosaid engine. 12: The method of claim 11 further including the step ofretaining said inert gas in said engine whereby corrosion on saidinternal surfaces is prevented. 13: The method of claim 11 wherein saidinert gas is selected from the group consisting of helium and nitrogen.14: The method of claim 11 further including the step of providing ananticorrosive fluid and mixing said anticorrosive fluid with said inertgas prior to dispersion of the resulting mixture into the engine coolingsystem. 15: The method of claim 14 wherein said anticorrosive materialis selected from the group consisting of fogging oil and vegetable oil.16: The product of the method of claim
 11. 17: An apparatus for purgingcorrosion inducing fluids from a mechanical system during storagecomprising: a source of inert gas having an outlet; a first couplingattached to said outlet; and a second coupling in fluid communicationwith the system whereby the first coupling is adapted to be removablycoupled to the second coupling. 18: The apparatus of claim 17 whereinthe source of inert gas comprises a pressurized tank. 19: The apparatusof claim 17 wherein the inert gas is selected from the group consistingof helium and nitrogen. 20: The apparatus of claim 17 further includinga pressure regulator attached to the outlet. 21: The apparatus of claim17 further including a source of anticorrosive fluid, said source ofanticorrosive fluid being in fluid communication with said source ofinert gas. 22: The apparatus of claim 21 further including a mixingdevice, said mixing device located at the fluid communication of theanticorrosive fluid and the inert gas. 23: The apparatus of claim 17wherein the first and second couplings are quick disconnect couplings.24: The apparatus of claim 17 further including a valve, said valvebeing attached to the inert gas outlet. 25: An apparatus for purgingcorrosion inducing fluids from a cooling system of an internalcombustion engine during storage comprising: a source of inert gashaving an outlet; a first coupling attached to said outlet; a secondcoupling in fluid communication with the cooling system whereby thefirst coupling is adapted to be removably coupled to the secondcoupling; and a source of anticorrosive fluid, said source ofanticorrosive fluid being in fluid communication with said source ofinert gas. 26: A method of inhibiting corrosion on the interior surfacesof an internal combustion engine cooling system during storagecomprising the steps of: providing a mixing device having at least twoinput ports and at least one output port; connecting a source ofanticorrosive fluid to at least one of the input ports of the mixingdevice; connecting a source of pressurized inert gas to at least one ofthe input ports of the mixing device; connecting the at least one outputport of the mixing device to an intake port formed in said engine;creating a mixture by combining said anticorrosive fluid and said inertgas in the mixing device; dispersing said mixture into said enginecooling system through said intake port formed in said engine; andpurging corrosion producing fluids from said engine as said mixture isdispersed into said engine. 27: An apparatus for purging corrosioninducing fluids from a mechanical system during storage comprising: asource of inert gas having an outlet; a first coupling attached to saidoutlet; a second coupling in fluid communication with the system wherebythe first coupling is adapted to be removably coupled to the secondcoupling; and a source of anticorrosive fluid, said source ofanticorrosive fluid being in fluid communication with said source ofinert gas.